Hybrid drive system

ABSTRACT

A hybrid-driven device includes an electric power storage device and a fuel cell. The hybrid-driven device can be a vehicle such as a motorcycle, scooter, watercraft, an automobile, and the like. The electric power storage device, such as a battery, and a fuel cell, can be formed into independent unitary modules, each having a controller. Each of the modules can be removably mounted as a unit to the vehicle. Additionally, each independent module can include sensors for detecting a state of the respective module. Each module can also include memory for storing data gathered by the sensors. The vehicle can also include a controller which controls the electrical power storage device and the fuel cell to provide smooth operation of the device.

This application is based on and claims priority to PCT/JP00/05660,filed Aug. 24, 2000, Japanese Patent Application No. 11/240791 filedAug. 27, 1999, Japanese Patent Application No. 11/242557 filed Aug. 30,1999, and Japanese Patent Application No. 11/246,493 filed Aug. 31,1999, the entire contents of which is hereby expressly incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a hybrid-driven device with a battery and afuel cell as power sources of a drive motor for mobile devices such asvehicles, watercrafts, and the like.

2. Background Art

A hybrid type electric car has been developed for the purpose ofreducing pollution generated by vehicles, which includes an electricmotor for driving the vehicle. Two kinds of batteries, for constantspeed running and high output running, are combined as power sources ofthe vehicle to increase travel distance for each charge and to provideefficient and stable power supply during constant speed running and highoutput running, such as acceleration. In such a hybrid-driven vehicle, asystem has been contemplated in which methanol is used as primary fuel,and a fuel cell is used as a power supply source. This system includes areformer and a shift reactor for processing carbon monoxide, and asecondary battery in addition to the power supply source, such as a leadbattery, for carrying peak load. In such a hybrid-driven vehicle, avehicle controller is provided for controlling the motor in an optimumcondition by supplying electric power efficiently in response to theoperating conditions after actuation of the power source. Modulesconstituting equipment such as a motor, a fuel cell and a battery areprovided with sensors for detecting data, such as temperature, rpm or astate of the voltage and current, corresponding to the modules necessaryfor drive control of the vehicle, respectively. The vehicle controllercalculates required electric power or expected travel distance accordingto the detected output, for charging/discharging of the battery and thefuel cell, and drive control of the motor, or the like.

In constructing such a control system, it is desirable for each moduleto be easily installed into the vehicle and so as to provide easy partsreplacement including that of related control system parts, for improvedapplication of modules, and also to receive reliable control data, formore reliable control.

In driving a vehicle using two power sources such as a battery and afuel cell described above, the vehicle controller calculates expectedtravel distance from the data on the residual amount of power sourcecapacities and fuel in the normal operating conditions of both powersources, makes an effective use of the power sources during runningwhile verifying reliable travel to the destination. The controller alsomakes proper use of the power sources, such as supplementary use of thebattery to compensate for the delayed output response of the fuel cellduring acceleration, so as to perform drive control of power sourcesthrough their controllers, for constant stable running.

However, if an abnormality occurs in the battery or the fuel cell,continuous use of the power sources might disable drive control based onthe data from the power source controller, preventing stable running,and the abnormal state might expand more widely due to delayed measuresagainst the abnormality, causing damage to other sections.

In view of the foregoing, it is a first object of this invention toprovide a hybrid-driven vehicle capable of effecting improved efficiencyof assembly and maintainability of modules forming a power system suchas a motor and power supply sources such as a fuel cell and a battery,as well as reliable control.

In addition, it is a second object of this invention to provide ahybrid-driven vehicle in which the states of two power sources aredetected during operation to calculate an approximate vehicle rangebased on the detection data, and the states of power sources aremonitored constantly during operation such that the vehicle is able totravel smoothly to the destination.

Further, it is a third object of this invention to provide ahybrid-driven vehicle in which in the event that an abnormality isdetected in either of the two hybrid drive power sources, the use of thepower source is stopped promptly to prevent expansion of the abnormalstate so as to cope with the abnormality immediately. Operation iscontinued using the other power source, for smooth drive control of thepower system.

SUMMARY OF THE INVENTION

In order to achieve the foregoing first object, a first aspect of theinvention includes a hybrid-powered vehicle having a first and a secondpower supply source, a main switch for switching on the power sources,and a device controller for controlling the device, wherein said powersystem and said first and second power supply sources are formed asintegrated module units, respectively, each module unit is provided witha module controller a sensor for detecting the state of the module, anda sensor configured to store data indicative of the detected state.

In this arrangement, equipment constituting the power system such as amotor, the first power supply source such as a fuel cell and the secondpower supply source such as a battery, are arranged as module units suchas a motor unit, a fuel cell unit and a battery unit, respectively, tobe combined integrally together with related equipment and components,and incorporated unit by unit in a device such as a vehicle. The moduleunits contain module controllers for controlling the respective modules.The module controllers have memory for storing detection data from statedetection means of the modules, so that each module unit is able toperform data communication with the device controller.

By arranging the motor, fuel cell and battery as module units containingcontrollers, respectively, efficiency of assembly work andmaintainability of modules are improved. Additionally control systemscorresponding to the modules are integrated for the respective modules,thereby providing improved reliability of the control, easy partsreplacement including that of the control system parts and improvedapplicability of modules with effective parts control.

In a preferred arrangement, the device controller is adapted to performbidirectional data communication with the module controllers.

In this arrangement, data is stored in each module controller. Thedevice controller can receive requisite data on request to the modulecontroller. Thus, the memory structure is simplified on the devicecontroller side and effective control can be performed on the samecommunication line for each module.

In another preferred arrangement, after a predetermined time has elapsedfrom a time when the main switch is turned off, preparation processingis performed on said first or said second power supply source for thenext operation.

In this arrangement, after a predetermined time has elapsed from a timewhen the main switch is turned off, it is determined whether thecapacity of the power supply source is optimized sufficiently for normaloperation. Optionally when operation is stopped and the main switch isturned off, residual capacity of the first or the second power supplysource is detected. Then, capacity-up processing is performed at a timeearlier than the time of the next driving schedule entered by the userby a length of time necessary to increase the detected residual electriccapacity up to an optimum value. Thus, the device can be held on standbyin an optimum condition such that operation can be started stably andreliably at the time of next running for continued normal operation.

In addition, in order to achieve the second object, another aspect ofthis invention may provide a hybrid-powered vehicle with a first and asecond power supply source as power sources for driving the vehicle,wherein an available amount of power supply by each of said first andsaid second power supply source is detected, and a controller isconfigured to calculate an approximate vehicle range from the availableamount of power supply.

In this arrangement, during operation, the available amount of powersupply of each of the first and the second power source, for example,residual capacity or residual fuel, is detected and the approximatevehicle range is calculated on the basis of the detected data. Thus,stable operation to the destination is verified and a prompt action canbe taken when the approximate vehicle range or the residual quantity isinsufficient.

In a preferred arrangement, this aspect of the invention ischaracterized in that said first power source is a fuel cell and saidsecond one a battery. The fuel consumption ratio of the fuel cell andthe capacity consumption ratio of the battery are calculated, and theapproximate vehicle range is calculated on the basis of theseconsumption ratios. If said residual fuel of the fuel cell and saidresidual capacity of the battery are not more than the respectivepredetermined setting values, warning is indicated.

In this arrangement, the hybrid power source preferably comprises a fuelcell and a battery (secondary battery). The fuel consumption ratio ofthe fuel cell is calculated from the traveled distance and the fuelconsumption, and the approximate vehicle range by the fuel cell iscalculated from the fuel consumption ratio and the residual amount offuel. Further, the capacity consumption ratio of the battery iscalculated from the traveled distance and the voltage drop of thebattery or the capacity consumption of the whole vehicle, and theapproximate vehicle range is calculated from the capacity consumptionratio and the residual capacity. In this case, if the residual fuel andthe residual capacity of the battery are not more than the respectivepredetermined values, warning is indicated and appropriate measures canbe taken such as refueling and battery change, or charging.

In still another preferred arrangement, this aspect of the invention ischaracterized in that the characteristic data of capacity correspondingto the current and voltage of the battery is provided beforehand. Thebattery capacity is calculated from the detection data on the current orvoltage of the battery, based on the characteristic data of capacity.

In this arrangement, the characteristic data of capacity correspondingto the current and voltage of the battery is stored beforehand in a ROM,etc. When the current or voltage of the battery is detected, the batterycapacity (residual capacity) at the time of detection is calculated fromthe stored characteristic data of capacity, based on the detection data.

In another preferred arrangement, this aspect of the invention ischaracterized in that after a predetermined time has elapsed after afirst detection data is obtained on said current or voltage, a seconddetection data is obtained on the current or voltage. The impedance iscalculated from the calculated capacity value based on the first and thesecond detection data.

In this arrangement, after a predetermined time has elapsed after thebattery capacity and the impedance are calculated on the basis of thefirst detection data, the capacity and the impedance are calculated onthe basis of the second detection data. The state of discharge of thebattery is identified from the impedance change. Taking account of thisimpedance change, the approximate vehicle range can be calculated onbasis of the residual capacity of the battery.

Further, in order to achieve the third object, a further aspect of theinvention can include a hybrid-driven device having a first and a secondpower supply source as power sources of a power system for driving thedevice. The first and second power supply sources are connected to saidpower system through first and second switches, respectively. A devicecontroller is configured to control the device according to theoperating conditions. The first and second power supply sources alsohave controllers, respectively. The controllers are adapted to detectabnormalities of the power supply sources and to store the detectiondata on abnormality. The device controller is adapted to performbidirectional communication with the controllers of the power supplysources to send/receive data or commands, and to cut off the powersupply source from said power system through the switches when saiddevice controller receives said detection data indicating anabnormality.

In this arrangement, the device controller which controls the wholedevice is adapted to perform data communication with controllers of thepower supply sources. If an abnormality occurs in any of the powersupply sources and the abnormality is detected by its controller, thedetection data is sent to the device controller, and the devicecontroller determines which supply source the abnormality happens in,and cuts off the abnormal power supply source from the power systemthrough the switches such as a relay. Thus, the use of the abnormalpower source is stopped promptly and operation is continued using theother power source while an appropriate action is taken against theabnormality, thereby minimizing damage.

The abnormality of the power supply source can be detected by detectingthe temperature and current or voltage of each power supply source.These values are determined to be abnormal when these values exceed therespective proper ranges. If such an abnormal state is detected, thedetection data on the abnormality is stored in the controller of theabnormal power source and sent from the controller to the devicecontroller on request.

In a preferred arrangement, this aspect of the invention ischaracterized in that the controller of each power supply source sendsto said device controller a request signal for stoppage of dischargingof the power supply source upon detection of abnormality of the powersupply source. When the controller receives the request signal, thedevice controller cuts off the power supply source from said powersystem through the switches.

In this arrangement, the controller of each power supply source sends asignal requesting stoppage of discharging to stop the use of the powersource upon detection of abnormality of the power source. The devicecontroller which received the request signal for stoppage of dischargingdetermines which power source the signal was sent from, and cuts off thepower source from the power system through the switches occurs. Thus,when an abnormality occurs in a power source, a command can be requestedfor stopping the use of the power source, from the abnormal power sourceside, through communication between the controllers of the power sourcesand the device controller, providing a prompter action to cope with theabnormality. The request signal for stoppage of discharging may besimply the detection data on abnormality. In this case, if anabnormality is detected, the detection signal is sent to the devicecontroller, and the device controller cuts off the abnormal power sourceaccordingly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a hybrid-driven vehicle accordingto an embodiment of this invention;

FIG. 2A is a side elevational view of a modification of the vehicleshown in FIG. 1, having a hydrogen supplying device;

FIG. 2B is a schematic view o the hydrogen supplying device shown inFIG. 2A;

FIG. 3 is block diagram of a control system of the hybrid-driven vehicleaccording to the embodiment of this invention;

FIG. 4 is a structural diagram of a portion of a fuel cell unit includedin the vehicle;

FIG. 5 is a structural diagram of a power source control system includedin the vehicle;

FIG. 6 is another illustration of the control system of thehybrid-driven vehicle;

FIG. 7 is a flowchart illustrating a control subroutine for operationduring standby of the hybrid-driven vehicle;

FIG. 8 is a flowchart illustrating a control subroutine for detectionand calculation of the state of the power source in the hybrid-drivenvehicle;

FIG. 9 is a flowchart illustrating a control subroutine for detectionand its indication of the residual quantities of the power sourcesduring running of the hybrid-driven vehicle;

FIG. 10 is a flowchart illustrating a control subroutine for capacitycontrol of the battery during running of the hybrid-driven vehicle; and

FIG. 11 is a graph of the capacity characteristics (percentage to themaximum capacity) corresponding to the current (I) and voltage (V) ofthe battery.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, an embodiment of this invention will be described below withreference to the drawings.

FIG. 1 is a general structural view of a hybrid-driven vehicle accordingto an embodiment of this invention. The hybrid-driven vehicle 1 of thisembodiment is applied to a motor bicycle. The hybrid-driven vehicle 1 isprovided with a hybrid-driven system 2. The hybrid-driven system 2comprises an electric motor unit 3, a transmission 4, a vehiclecontroller 5, a battery unit 6 and a fuel cell unit 7.

The fuel cell unit 7, comprised mainly of a fuel cell and a reformer, isdisposed rearwardly of a seat 8 and upwardly of a drive wheel 9. Infront of the seat 8 and between the seat and a front fork 12 forsteering a steering wheel 11, is disposed a methanol tank 13. Themethanol tank 13 is provided with a filler cap 14.

The hybrid system comprises a fuel cell in the fuel cell unit 7 and abattery in the battery unit 6 and is adapted to drive an electric motorin the electric motor unit 3 to rotate the drive wheel 9.

FIG. 2(A) illustrates a modification of the hybrid-driven motor bicycle1 illustrated in FIG. 1, and FIG. 2(B) is a structural view of ahydrogen supplying device for the fuel cell.

The hybrid-driven vehicle 1 a has a vehicle controller 5 a and a batteryunit 6 a under a seat 8 a; under the vehicle controller 5 a is providedan electric motor unit 3 a; and in front thereof is provided a fuel cellunit 7 a comprised mainly of a fuel cell. On a carrier to the rear ofthe seat 8 a is provided a hydrogen supplying device 15 a for supplyinghydrogen for power generation to the fuel cell unit 7 a.

The hydrogen supplying device 15, as shown in FIG. 2(B), is providedwith a hydrogen tank 16 or “bomb” (i.e., a vessel for storing compressedhydrogen)together with a methanol tank 13, and with a fan 17 and aburner 18 for supplying combustion air, and further with a reformer 19for producing hydrogen through catalyst, with primary fuel being heatedand vaporized.

FIG. 3 is a schematic block diagram of the hybrid-driven vehicleaccording to this invention.

The hybrid-driven vehicle 1 is provided with a main switch SW1, a seat8, a stand 20, a foot rest 21, an acceleration grip 22, a brake 23, adisplay 24, a lamp unit 25 including a light, a blinker, etc, a userinput device 26, a non-volatile memory 27 and a timer 28, and furtherwith an electric motor unit 3, a transmission 4, a vehicle controller 5,a battery unit 6 and a fuel cell unit 7.

ON/OFF signals are sent from the main switch SW1 to the vehiclecontroller 5 to drive the motor-powered vehicle. To the seat 8, stand20, foot rest 21 and brake 23 are fitted sensors S1-S4, respectively.“ON/OFF” signals corresponding to seating/non-seating, use/non-use ofthe stand, feet-resting/non feet-resting and ON/OFF of the brake aresent from the respective sensors S1-S4 to the vehicle controller 5,where the respective operating conditions are detected.

The accelerator grip 22 includes output setting means. To theaccelerator grip 22 is fitted an accelerator opening sensor S5, fromwhich signals indicative of accelerator opening are sent to the vehiclecontroller 5 through a gripping manipulation of the user. The electricmotor is controlled according to accelerator opening. The vehiclecontroller 5 includes control means for controlling the output of theelectric motor based on the output setting value from the output settingmeans constituted by the accelerator grip 22.

The user is able to input various data from a user input device 26 tothe vehicle controller 5 to change, for example, the operatingcharacteristics of the vehicle. Also, data are transferred between thenon-volatile memory 27, timer 28 and the vehicle controller 5. Forexample, data is stored to the non-volatile memory 27 regardinginformation on the operating conditions of the vehicle at a time whenthe vehicle stops, and the vehicle controller 5 reads the information onthe stored operating conditions for control when operation is started orre-started.

The display 24 is driven by indicator-ON/OFF signals from the vehiclecontroller 5 and the operating conditions of the motor-powered vehicleare indicated on the display 24. The lamp unit 25 including a light,blinker, etc is comprised of lamps 25 b of the light, blinker, etc.Activation-ON/OFF signals from the vehicle controller 5 drive a DC/DCconverter 25 a to light the lamps 25 b.

The electric motor unit 3 is provided with a motor driver 30, anelectric motor 31 connected to the drive wheel 9, an encoder 32, aregenerative current sensor S11 and regenerative energy control means33. The motor driver 30 controls the electric motor 31 through dutysignals from the vehicle controller 5, and the drive wheel 9 is drivenby the output of the electric motor 31. The encoder 32 detects theposition of the magnetic poles and the number of revolution of theelectric motor 31. Information on the motor speed from the encoder 32 isstored in a memory in the motor driver 30 to be sent to the vehiclecontroller 5 as required. Output of the electric motor 31 is changed inits speed by the transmission 4 to drive the drive wheel 9. Thetransmission 4 is controlled by speed-change command signals from thevehicle controller 5. The electric motor 31 is provided with a motorvoltage sensor or a motor current sensor S7, and information on thevoltage and current of the motor is stored in a memory in the motordriver to be sent to the vehicle controller 5 as required.

The battery unit 6 is provided with a battery 60, a battery controller61 and a battery relay 62. The fuel cell unit 7 is provided with a fuelcell 70 constituting power generating means, a fuel cell controller 71,a reverse current prevention element 72 and a fuel cell relay 73. Thereis also provided a first power supply path L1 allowing supply of theoutput current from the fuel cell 70 to the battery 60 and a secondpower supply path L2 allowing supply of the output current from thebattery 60 to the electric motor 31. Electric power is supplied from thefuel cell through an electric power regulating section 80.

The battery controller 61 is provided with detection means for detectingthe charging state of the battery 60. The detection means is comprisedof a battery temperature sensor S12, a battery voltage sensor S13 and abattery current sensor S14. Information from these sensors is stored ina memory in the battery controller 61 to be entered in the vehiclecontroller 5 as required. The battery relay 62 is activated by ON/OFFsignals from the vehicle controller 5 to control electric power supplyfrom the second power supply path L2.

Communication data are sent from the vehicle controller 5 to the fuelcell controller 71. The fuel cell controller 71 controls the fuel cell70 on the basis of the data from the controller 5. The fuel cellcontroller 71 is provided with detection means for detecting the stateof the fuel cell 70. The detection means is comprised of varioustemperature sensors S21, a fuel cell voltage sensor S22 and a fuel cellcurrent sensor S23. Information from these sensors is stored in a memoryin the fuel cell controller 71 to be entered in the vehicle controller 5as required. The fuel cell relay 73 is connected to the fuel cellcontroller 71 through the reverse current prevention element 72 whichcan be a rectifier diode, for example. The element 72 is activated byON/OFF signals from the vehicle controller 5 to control electric powersupply from the first power supply path L1.

FIG. 4 is a structural diagram of a portion of a fuel cell according toan embodiment of this invention.

The fuel cell unit 7 in this embodiment comprises a methanol tank 102, areformer 103, a shift converter 104, a selective oxidation reactor 105,a fuel cell 70, a moisture collecting heat exchanger 107, a water tank108 and the fuel cell battery controller 71. The fuel cell controller 71is connected to the devices such as valves, pumps and fans, and sensors.The reformer 103, shift converter 104, selective oxidation reactor 105and fuel cell 70 are provided with temperature sensors Tr, Tb, Ts, Tp,and Tc. The temperature of these components is controlled by the fuelcell battery controller 71 (FIG. 3) through temperature detection.

The reformer 103 is provided with a burner 110, an evaporator 111 and acatalyst layer 112. To the burner 110, methanol is supplied from themethanol tank 102 by a burner pump 113. The burner pump 113 is activatedthrough temperature detection by the temperature sensor Tb. Air from aburner fan 114, and the evaporator 111 is heated by combustion action ofthe mixture. The double circle in the figure represents an air inlet.Methanol is supplied to the evaporator 111 from the methanol tank 102 bythe methanol pump 115. Water is fed from the water tank 108 by the waterpump 116 and is mixed with the methanol therein. The burner 110 heatsthe evaporator 111 to vaporize the fuel mixture of methanol and water,and the vaporized fuel mixture in the evaporator 111 is supplied to thecatalyst layer 112.

To the burner 110 is supplied surplus (or bypassing) hydrogen from thefuel cell 70 through a line 201 for combustion. The combustion heat ofthe burner 110 vaporizes primary fuel (raw material) composed ofmethanol and water, and heats the catalyst layer 112 to maintain itstemperature at a value required for catalytic reaction. Combustion gas,and air not involved in the reaction, are discharged to the outsidethrough an exhaust passage 202.

The catalyst layer 112 is made, for example, of Cu-base catalyst, andresolves the mixture of methanol and water into hydrogen and carbondioxide at a catalyst reaction temperature of about 300° C. as follows:

CH3OH+H2O→3H2+CO2

In the catalyst layer, a very small amount (about 1%) of carbon monoxideis produced:

CH3OH→2H2+CO

Since this CO is adsorbed by catalyst in the cell 70 and lowerselectromotive force reaction, its concentration is lowered in the shiftconverter 104 and the selective oxidation reactor 105 in a latter stage,and in the cell 70, to the order of one thousand to some tens of ppm.

In the shift converter 104, carbon monoxide in the resolved gas isturned to CO2 at a reaction temperature of about 200° C. in thefollowing chemical reaction by surplus water vapor:

CO+H2O→H2+CO2

wherein CO concentration is lowered to the order of about 0.1%.

In the selective oxidation reactor 105, CO is further changed chemicallyto CO2 at a catalyst temperature of about 120° C. using platinum-basecatalyst in the oxidation reaction as:

2CO+O2→2CO2

and its concentration is reduced further to {fraction (1/10)} of theprevious value or smaller. Thus, the CO concentration in the cell 70 canbe lowered to the order of some tens of ppm.

The reformer 103 allows raw material to be reformed so as to producehydrogen as described above, and the hydrogen acquired is supplied tothe fuel cell 70 through the shift converter 104 and the selectiveoxidation reactor 105. A buffer tank 117 is provided between thereformer 103 and the shift converter 104 for absorbing pulsations andpressure changes caused by the switching of valves 117 a, 117 b. Thehydrogen is returned to the burner 110 through activation of theseswitching valves 117 a, 117 b. The shift converter 104 is cooled by acooling fan 118 in accordance with temperature detection by thetemperature sensor Ts. Cooling air is discharged to the outside throughan exhaust passage 203.

Between the shift converter 104 and the selective oxidation reactor 105is provided a buffer tank 124 and switching valves 124 a, 124 b.Hydrogen is returned to the burner 110 through activation of theseswitching valves.

Hydrogen sent from the shift converter 104 is mixed with air fed by areaction air pump 119 to be supplied to the selective oxidation reactor105. The selective oxidation reactor 105 is cooled by a cooling fan 120in accordance with temperature detection by the temperature sensor Tp.The cooling air is discharged to the outside through an exhaust passage204.

Between the selective oxidation reactor 105 and the fuel cell 70 isprovided a buffer tank 121 and switching valves 121 a, 121 b. Hydrogenis returned to the burner 110 in the reformer 103 through activation ofthese switching valves. As a result of the flow control achieved by theswitching of valves 1171, 117 b, 124 a, 124 b, 121 a, 121 b, the amountof hydrogen supplied to the fuel cell 70 can be regulated forelectromotive force control. Excessive oxygen is supplied to the fuelcell 70 in this case, so that the electromotive force is controlledaccording to the amount of hydrogen supplied thereto.

Such an electromotive force control is performed as follows: requiredelectromotive force is calculated by the vehicle controller 5 based onthe data from sensors S21-S23 and the detected data on the operatingconditions from other various sensors. The desired flow rate of eachswitching valve is calculated by the vehicle controller 5 or the fuelcell controller 71 based on the calculation results, taking account ofthe time lag required for the hydrogen quantity in the cell to bechanged after activation of the switching valve, on the basis of whichON/OFF control or opening control of each switching valve is performedby the fuel cell controller 71. In this case, a larger supply quantityof the primary fuel such as methanol may increase the amount ofevaporation of hydrogen to thereby increase the electromotive force, inwhich case time lag is produced by the time required for hydrogen toincrease sufficiently enough to participate in power generation. Such atime lag is compensated by electric power from the battery.

To the fuel cell 70, water is supplied from the water tank 108 by acooling and humidifying pump 122, and air is supplied from the moisturecollection heat exchanger 107 by a pressurizing air pump 123 inaccordance with temperature detection of the temperature sensor Tc.Using the water, air and hydrogen, power generation is performed in thefuel cell 70, as described below.

The fuel cell 70 is configured such that electrodes are each formedwith, for example, a platinum-base porous catalyst layer (not shown)provided on both sides of a cell film (not shown) with a cooling andhumidifying water passage 205 formed therein. To one electrode, issupplied hydrogen from the selective oxidation reactor 105 through ahydrogen passage 206. Oxygen (air) is supplied to the other electrodethrough an oxygen passage 207. Hydrogen ions move from the hydrogenpassage 205 of the hydrogen side electrode to the oxygen side electrodethrough the cell film and are combined with oxygen to form water. Themigration of electrons (−) associated with the migration of the hydrogenions (+) allows the electromotive force to be generated between theelectrodes.

This electromotive force generation is a heat development reaction, andfor the purpose of cooling and smooth migration of hydrogen ions to theoxygen side electrode, water is supplied from the water tank 108 to thewater passage 205 in the cell film between both electrodes by the pump122. The water which has passed through the water passage 205 increasesin temperature, exchanges heat with air in the heat exchanger 107 andreturns to the water tank 108. The water tank 108 is provided with aradiation fins 208 for cooling water. Numeral 209 designates an overflowpipe.

Air is introduced to the heat exchanger 107. The air, after being heatedby thermal communication with the water is supplied to the oxygenpassage 207 by the air pump 123. As a result of the hot air beingsupplied, the combining reaction with hydrogen ions in the fuel cell 70is accelerated, providing effective electromotive force reaction.Therefore, an air inlet (shown in the figure by a double circle) ispreferably provided in the vicinity of the selective oxidation reactor105 or the catalyst layer 112 where the foregoing high temperaturecatalytic reaction takes place.

Oxygen in the air passing through the oxygen passage 207 is combinedwith hydrogen ions is turned into water, and is collected in the watertank 108. The surplus air (oxygen and nitrogen) is discharged to theoutside through an exhaust passage 210.

Water used in the fuel cell 70 and water produced by power generation asdescribed above, exchanges heat with cooling air in the moisturecollecting heat exchanger 107 and is returned to the water tank 108.Also, the surplus hydrogen used for power generation in the fuel cell 70is returned to the burner 110 of the reformer 103 through a valve 211and a line 201.

As described above, in the fuel cell unit 7, by means of the reformer103 in which the evaporator 111 heated by the burner 110 and rawmaterial vaporized by the evaporator 111 is supplied to the catalystlayer 112, the raw material is reformed to produce hydrogen. Thehydrogen acquired is supplied to the fuel cell 70 through the shiftconverter 104 and the selective oxidation reactor 105 for powergeneration. In this case, hydrogen acquired from the selective oxygenreactor 105 may be stored, as shown in FIG. 2(B), temporarily in thehydrogen tank 16.

The output of the fuel cell 70, as shown in FIG. 3, is connected to thepower regulating section 80 through the reverse current preventionelement 72 and the fuel cell battery relay 73. The regulating section 80is connected to the battery 60 and the electric motor 31.

FIG. 5 is a block diagram of the power source control system of thehybrid-driven vehicle 1, 1 a according to this invention.

The vehicle controller 5 is connected to the electric motor unit 3,battery unit 6, and fuel cell unit 7 through bidirectional communicationlines 220, 221, 222, respectively. The fuel cell unit 7 is connected tothe electric motor unit 3 through a (+) side current line 223 a and a(−) side current line 223 b. On the (+) side current line 223 a isprovided a switch 225. This switch 225 is turned ON and OFF by thevehicle controller 5.

The battery unit 6 is connected to the electric motor unit 3 through a(+) side current line 224 a and a (−) side current line 224 b which arecoupled to the (+) side current line 223 a and (−) side current line 223b, respectively. On the (+) side current line 224 a is provided a switch226. This switch 226 is turned ON and OFF by the vehicle controller 5.

The electric motor unit 3 is a unit in which a controller (motor driver30), an encoder and sensors, as well as an electric motor 31 (FIG. 3),are integrated together as a module. Such an electric motor unit 3 canbe mounted detachably on a vehicle as a unitary component. Therefore,the bidirectional communication line 220 and the current lines 223 a,223 b, 224 a, 224 b are each connected to the motor driver 30 as acontroller of the electric motor unit 3 through the respective couplers(not shown).

The motor driver 30 has a memory, and detected data such as theoperating conditions of the electric motor unit 3 (for example, numberof revolutions), throttle opening, running speed, request load,temperature and shift position are sent to the vehicle controller 5 toupdate the memory in the vehicle controller 5 for storage.

The battery unit 6 is a unit in which a battery controller 61, sensorsS12-S14 and a relay 52, as well as a battery 60 as shown in FIG. 3, areintegrated together as a module. Such a battery unit 6 can be mounteddetachably on a vehicle as a unitary component. Therefore, thebidirectional communication line 221 and the current lines 224 a, 224 bare connected to the battery controller 61 of the battery unit 6 throughcouplers (not shown).

The battery controller 61 has a memory, to which is stored dataregarding the battery unit conditions such as temperature, voltage andcurrent, and the residual capacity of the battery 60 while updatedconstantly. Thus, the data can be transferred through bidirectionalcommunication between the battery controller and the vehicle controllerto supply required power during running when the battery 60 is replaced,the residual capacity can be immediately recognized by the vehiclecontroller 5 for processing of expected travel distance, etc.

The fuel cell unit 7 is a unit in which a fuel cell controller 71,sensors S21-S23 (FIG. 3) and a relay 52, as well as the fuel cell 70,reformer, etc, are integrated together as a module. Such a fuel cellunit 7 can be mounted detachably on a vehicle as a unitary component.Therefore, the bidirectional communication line 222 and the currentlines 223 a, 223 b are connected to the fuel cell controller 71 of thefuel cell unit 7 through couplers (not shown).

The fuel cell controller 71 has a memory, to which is stored dataregarding the fuel cell unit conditions such as temperature, voltage andcurrent, and the capacity (specifically, the residual fuel in themethanol tank) of the fuel cell while updated constantly. Thus, the datacan be transferred through bidirectional communication between the fuelcell controller and the vehicle controller to supply required powerduring running, and processing of expected travel distance, etc, can beperformed.

Although in the embodiment in FIG. 5, a fuel cell 70 and a battery 60are used as two power supply sources constituting the hybrid-drivenvehicle, two fuel cells or two batteries (second batteries) may be used,or an engine type generator or a capacitor may be used. In addition,this invention can be applied to watercrafts or other devices inaddition to vehicles.

FIG. 6 is an illustration of data communication in the control system ofthe hybrid-driven vehicle 11 a according to yet another aspect of thisinvention.

The vehicle controller 5 transmits, to the electric motor unit 3 (motordriver (controller of the electric motor) 30, encoder 32 and othersensor group), battery controller 61 and fuel cell controller 71,request signals of various data stored in the memories of thecontrollers 30, 61, 71. In response, required data are sent back to thevehicle controller 5 from the sensor group of the electric motor unit 3,and the controllers 30, 61, 71. The contents of the data includeinformation such as temperature, voltage, current, error information andcapacity, and control information such as output request.

The vehicle controller 5 calculates, on the basis of the data from thesensor group and the controllers 30, 61, 71, the optimum amount of driveto the units, the data on the amount of drive are sent, as operationcommand data, to the motor driver 30 and controllers 30, 61, 71 for thecontrol of the electric motor unit 3, battery unit 6 and fuel cell unit7.

In such bidirectional data communication, according to the presentaspect of the invention, when an abnormality occurs in the battery unit6 or the fuel cell unit 7, the abnormality is detected by the batterycontroller 61 or the fuel cell controller 71, and the detection dataregarding the abnormality is sent to the vehicle controller 5. Thevehicle controller S determines accordingly whether the abnormalityoccurred in the battery unit 6 or the fuel cell unit 7, and cuts off theswitch 225 or 226 (FIG. 5) of the power source where the abnormality isdetected, to stop power supply from the abnormal power source to themotor. The switches 225, 226 can be the fuel cell relay 73 and thebattery relay 62 of FIG. 3, respectively. The battery unit 6 isdetermined to be abnormal when the detection value of any of the batterytemperature sensor S12, battery voltage sensor S13 and battery currentsensor S14 is excessively large or small beyond the range of normaldetection values which are stored as detection data on abnormality inthe memory of the battery controller 61.

Similarly, the fuel cell unit 7 is determined to be abnormal when thedetection value of any of the temperature sensor S21, fuel cell voltagesensor S22 and fuel cell current sensor S23 is excessively large orsmall beyond the range of normal detection values which are stored asdetection data on abnormality in the memory of the fuel cell controller71.

The vehicle controller 5 constantly sends to the controllers 61, 71 datarequests including the detection data on abnormality, and if an abnormalstate exists, the data is sent back to the vehicle controller 5. Whenthe vehicle controller receives the detection data indicating anabnormality, the connection between the power source and the motor iscut off as described above.

If an abnormality is detected, the battery controller 61 or the fuelcell controller 71 that detected the abnormality, may send a requestsignal for stoppage of discharging of the abnormal battery or the fuelcell, to stop the use of the battery or the fuel cell. The vehiclecontroller 5 that has received the request signal for stoppage ofdischarging, determines whether the battery or the fuel cell needs tostop discharging, and cuts off the switch 225 or 226 of the abnormalpower source to stop the use of the power source.

Such bidirectional communication of the detection data regardingabnormality allows a prompt action against such abnormalities at thetime of occurrence of abnormality in the power source. In this case,even if the failure of the sensor itself is detected as an abnormalityof the power source, it can be handled as an abnormal state.

FIG. 7 is a flowchart of control of the power supply system duringnon-running of the hybrid-driven vehicle according to a further aspectof the invention.

The operation at each step is as follows:

S101: It is detected whether or not the main switch for power supply tothe vehicle 1, 1 a is OFF, to determine the end of use of the vehicle 1,1 a. If the vehicle 1, 1 a is in use (in the state of running),necessary data communication is performed between the vehicle controller5 and each controller 71, 61 of the fuel cell unit 7 and the batteryunit 6, as shown previously in FIG. 6, for drive control of the vehicle1, 1 a according to the control program during running.

S101-A: a setting value of the timer count is determined based on thetime of the next running and the current residual amount. That is, ifthe main switch SW1 is OFF, the timer is operated, and the need ofdischarging or charging is determined from the current battery capacity.Further, a length of time necessary for a discharging or a chargingoperation is calculated. A setting time is determined such that it isearlier than the time of the next running by the foregoing necessarylength of time plus a margin (for example, a few to some tens ofminutes). The time difference between the time of switching-off of themain switch and the setting time is calculated as a setting value.

S102: If the main switch is OFF, an end signal is sent from the vehiclecontroller to each controller of the motor unit 3, fuel cell unit 7 andbattery unit 6.

S103: The elapsed time after switching-off of the main switch is countedby the timer.

S104: It is determined whether or not the elapsed time is a givensetting value (the value calculated at Step S101-A). If it is less thanthe setting value, counting is continued till the setting value isreached.

S105: After the given setting time has elapsed since switching-off ofthe main switch SW1, the capacity of the fuel cell and the battery isdetected. In this case, residual fuel in the methanol tank can bedetected as an indication of the residual capacity of the fuel cell

S106: The detected battery capacity is compared with a given settingvalue A. The setting value A is set to a minimum capacity required forsmooth starting of the next running of the vehicle 1, 1 a.

S107: If the battery capacity is not larger than the setting value A,the fuel cell unit 7 is operated through the fuel cell controller 71, tocharge the battery 60 so that the battery capacity becomes larger thanthe setting value A.

S108: If the battery capacity is larger than the setting value A, thebattery capacity is compared with a given setting value B.

S109: If the battery capacity is larger than the setting value B, adischarging command is sent to the battery controller, and the batteryis discharged until the capacity reaches the setting value B.

S110: If the battery capacity is not larger than the setting value B(larger than the setting value A), the fuel cell 70 and the battery 60are held on standby for starting of the next running of the vehicle 1, 1a.

As in FIG. 9, the vehicle controller 5 transmits or receives severalkinds of data to or from the battery controller 61 and the fuel cellcontroller 71.

S111: Data regarding the distance traveled by the vehicle 1, 1 a fromthe start of running is obtained. The data, which is detected by adistance detection sensor located on the axle (not shown), is written ina RAM (or non-volatile memory) of the battery controller 61 or the fuelcell controller 71, or in a RAM (or non-volatile memory) provided in thevehicle controller 5, for reading.

S112: The fuel consumption ratio is calculated on the basis of the dataon the quantity of methanol fuel consumed from the start (differencebetween the current residual fuel in the methanol tank and the residualfuel at the start of operation) and the data regarding the traveleddistance. This fuel consumption ratio is used to calculate theapproximate vehicle range provided by the fuel cell 70.

S113: The capacity consumption ratio for the whole vehicle 1, 1 a iscalculated on the basis of the battery capacity data (the currentbattery capacity) and the traveled distance. This capacity consumptionratio is used to calculate the approximate vehicle range provided by theresidual battery capacity and residual methanol.

The approximate vehicle range can be calculated by obtaining the data onthe capacity consumption of the whole vehicle 1, 1 a including the fuelconsumption and the battery consumption, and calculating the capacityconsumption ratio of the vehicle 1, 1 a from this capacity consumptionand the traveled distance.

For example, if the consumption ratio of the electric power supplier(fuel cell) is 100 cc/Ah and the capacity consumption ratio is 2.0km/Ah, the approximate vehicle range in the case of the residual fuel of3000 cc and the residual battery capacity of 5.0 A/h is:

(3000/100+5.0)×2.0=70 km.

S114: It is determined whether the residual methanol fuel in the fueltank is not more than a given setting value.

S115: If the amount of methanol fuel is more than the given settingvalue, the residual quantity is displayed on a fuel indicator panel asusual.

S116: If the amount of methanol fuel is not more than the given settingvalue, it is determined whether the residual battery capacity is notmore than the given setting value. If the residual battery capacity ismore than the setting value, then at S115, the residual battery capacityis displayed on the indicator panel as usual, as well as the amount ofthe methanol fuel.

S117: If the residual quantity of the methanol fuel or the battery isnot more than the respective given setting value, warning is indicatedon the indicator panel.

S118: If the amount of fuel detected at S114 exceeds the setting value,it is determined whether the residual battery capacity is not more thanthe given setting value. If the residual battery capacity is not morethan the setting value, warning is indicated (Step S117), and if it ismore than the setting value, the residual quantity is indicated as usual(Step S115).

FIG. 10 is a flowchart of a preferred control subroutine for controllingthe battery capacity during running. FIG. 11 is a graph of the capacitycharacteristics (percentage to the maximum capacity) corresponding tothe current (I) and voltage (V) of the battery.

As described above, the vehicle controller 5 performs bidirectional datacommunication with the battery controller 61.

S121: The first detection data on the voltage and/or current of thebattery is read from the battery controller 61 to be sent to the vehiclecontroller 5. The vehicle controller 5 stores the data on the capacitycharacteristics of FIG. 11, as a map beforehand in a ROM, etc. From thevoltage or current data, the degree of consumption (percentage to themaximum capacity) of the battery capacity at a given time is found fromthe map in the graph of the capacity characteristics. This batterycapacity changes, for example, over a certain time of use, as shown inthe figure by the arrow.

S122: After the first data on the current and voltage is obtained, thetimer begins counting.

S123: It is determined by the timer whether or not the given settingtime is reached. Timer counting is continued until the setting time isreached.

S124: After the setting time has elapsed, the second data on the currentand/or voltage of the battery is read from the battery controller 61 tobe sent to the vehicle controller 5.

S125: The degree of consumption of the battery capacity is found fromthe graph of FIG. 11, based on the foregoing first data and the seconddata, and the impedance is calculated. The deterioration of the batteryis determined from the impedance change.

Alternatively, during use of the battery, the current and voltage can bedetected in an approximately constant current state generated by quickchange over of the battery switch (FET, etc), and the residual batterycapacity and the impedance may be calculated from the current andvoltage characteristics in this constant current state.

Industrial Applicability

According to this embodiment as described above, as a result that themotor, fuel cell and battery are arranged as module units containingcontrollers, respectively, the efficiency of assembling andmaintainability of modules are improved and control systemscorresponding to the modules are integrated for the respective modules,thereby providing improved reliability of the control, easy partsreplacement including that of the control system parts and improvedapplicability of modules with effective parts control.

In addition, if the device (vehicle) controller which controls the wholedevice is adapted to perform bidirectional data communication with themodule controllers such as the motor, battery and fuel cell, then datais stored in each module controller and the device controller canreceive requisite data on request to the module controller. Thus, thememory structure is simplified on the device controller side, andeffective control can be performed using the same communication line foreach module.

Further, if after a predetermined time has elapsed from the time themain switch is turned off, preparation processing is performed on thepower supply sources such as the fuel cell and the battery, for the nextoperation. After the predetermined time has elapsed, the capacity of thefuel cell or the battery is detected so that it can be optimizedsufficiently for normal operation. Once optimized, the device can beheld on standby in an optimum condition for starting stably and reliablyat the time of next running, for continued normal operation.

Furthermore, during operation, the available amount of power supply ofeach of the first and the second power source constituting the hybriddevice, for example, residual capacity or residual fuel, is detected.The expected travel distance of the mobile body is calculated on thebasis of the detected data Stable operation to the destination isverified and action can be taken when the expected travel distance orthe residual quantity is insufficient.

Moreover, the use of an abnormal power source can be stopped promptlyand operation is continued using the other power source while anappropriate action is taken against the abnormality, thereby minimizingdamage.

What is claimed is:
 1. A hybrid powered vehicle comprising a vehiclebody, a propulsion unit configured to propel the vehicle body, a batteryunit configured to supply sufficient power to the propulsion unit topropel the vehicle body, the battery unit comprising a batteryconfigured to store electric power, a battery unit controller, a batteryunit sensor configured to detect at least one operational characteristicof the battery and emit a signal including battery data indicative ofthe operational characteristic of the battery, and a battery unit memoryconfigured to store the battery data, the battery unit being formed asintegral unit, a fuel cell unit configured to supply sufficient power tothe propulsion unit to propel the vehicle body, the fuel cell unitcomprising a fuel cell configured to generate electrical power from aflow of fuel therethrough, a fuel cell unit controller, a fuel cell unitsensor configured to detect at least one operational characteristic ofthe fuel cell and emit a signal including fuel cell data indicative ofthe operational characteristic of the fuel cell, and a fuel cell unitmemory configured to store the fuel cell data, the fuel cell unit beingconfigured as an integral unit, and a main controller configured toselectively supply power from the battery unit and the fuel cell unit tothe propulsion unit.
 2. The vehicle according to claim 1 additionallycomprising a first bidirectional data connection between the maincontroller and the battery unit controller and a second bidirectionaldata connection between main controller in the fuel cell unitcontroller.
 3. The vehicle according to claim 1, wherein at least one ofthe fuel cell unit and the battery unit is removable from the vehicle asan integrated unit.
 4. The vehicle according to claim 1, wherein thebattery unit controller is configured to determine an amount ofelectrical power in the battery, the fuel cell unit controller beingconfigured to determine an amount of electrical power available from thefuel cell, the main controller being configured to emit a warning signalif the amount of electrical power available from at least one of thebattery unit and the fuel cell unit is below a predetermined amount. 5.The vehicle according to claim 1 additionally comprising a battery unitswitch selectively connecting the battery unit with the main controllerand a fuel cell unit switch selectively connecting the fuel cell unitwith the controller, the main controller being configured to detect anabnormality in the battery unit and the fuel cell unit, and to operateat least one of the switches if an abnormality is detected in one of thebattery unit and the fuel cell unit.
 6. A hybrid-powered vehiclecomprising a vehicle body, a propulsion device configured to propel thevehicle body, first and second power supply sources being different fromeach other, each power supply source being configured to supplysufficient power to drive the propulsion device, a controller configuredto determine an amount of power available from each of the first andsecond power supply sources, the controller being configured tocalculate an approximate travel range of the vehicle based on the amountof power available from the first and second power supply sources,wherein the first power source is a fuel cell and the second powersource is a battery, the controller being configured to determine a fuelconsumption ratio of the fuel cell and a capacity consumption ratio ofthe battery, the controller also being configured to determine theapproximate travel range based on the fuel consumption ratio and thecapacity consumption ratio.
 7. The vehicle as set forth in claim 6,wherein the controller is configured to emit a warning if theapproximate travel range is not more than a predetermined travel range.8. The vehicle as set forth in claim 6 additionally comprising a memoryincluding data regarding capacity of the battery corresponding to acurrent and a voltage of the battery, the controller being configured tocalculate battery capacity based on the data and at least one of thecurrent and voltage of the battery.
 9. The vehicle as set forth in claim8, wherein the controller is configured to obtain a first detection dataregarding at least one of current and voltage of the battery and asecond detection data regarding at least one of current and voltage ofthe battery after a predetermined time period has elapsed from when thefirst detection data was obtained.
 10. The vehicle as set forth in claim9, wherein the controller is configured to determine an impedance of thebattery from the calculated capacity value based on the first and thesecond detection data.
 11. A hybrid-powered vehicle comprising a vehiclebody, a propulsion device configured to propel the vehicle body, firstand a second power supply sources being different from each other, eachpower supply source being configured to supply sufficient power to drivethe propulsion device, a controller configured to determine an amount ofpower available from each of the first and second power supply sources,the controller including means for calculating an approximate travelrange of the vehicle based on the amount of power available from thefirst and second power supply sources, wherein the first power source isa fuel cell and the second power source is a battery, the means forcalculating including means for determining a fuel consumption ratio ofthe fuel cell and a capacity consumption ratio of the battery, the meansfor calculating including means for determining the approximate travelrange based on the fuel consumption ratio and the capacity consumptionratio.
 12. The vehicle as set forth in claim 11, wherein the controllerincludes means for emitting a warning if the approximate travel range isnot more than a predetermined travel range.
 13. The vehicle as set forthin claim 11 additionally comprising a memory including data regardingcapacity of the battery corresponding to a current and a voltage of thebattery, the controller being configured to calculate battery capacitybased on the data and at least one of the current and voltage of thebattery.
 14. The vehicle as set forth in claim 13, wherein thecontroller includes means for obtaining first and second detection dataregarding at least one of current and voltage of the battery with apredetermined time period delay between obtaining the first and seconddetection data.
 15. The vehicle as set forth in claim 14, wherein thecontroller includes means for determining an impedance of the batteryfrom the calculated capacity value based on the first and the seconddetection data.